Introducer system having kink resistant splittable sheath

Abstract

This invention relates to a flexible kink resistant introducer system for introducing an elongated object into the venous system and especially for introducing a cardiac pacemaker lead. The introducer system features a sheath having a kink resistant section allowing the sheath to be bent in that region and still allow a lead to be introduced therethrough. The kink resistant section comprises a series of bellows or pleats. The bellows or pleats may further be arranged to form a screw about a portion of the sheath to thereby permit the sheath to be screwed into body tissue. The sheath preferably is constructed to readily tear in a longitudinal direction and thus permits the system to be removed from the venous system without having to withdraw the sheath over an end of the pacemaker lead.

What is claimed is: 
     
       1. An introducer system for use with a catheter or lead comprising: a sheath having a first end and a second end, said sheath being compatible for insertion within a body, said first end configured to insert said sheath within said body with said second end extending out of said body, said sheath having a central lumen configured to permit introduction of at least one lead or catheter therethrough;   a flexible kink resistant section located along said sheath;   means for permitting removal of said sheath from said lead or catheter disposed therethrough without requiring said sheath to be removed from an end of said lead or catheter disposed therethrough; and   a dilator having a first end and a second end, said first end of said dilator being tapered, said dilator configured to be disposed through said central lumen of said sheath.   
     
     
       2. The introducer system of claim 1 wherein said means for permitting removal of said sheath comprises means for splitting said sheath away from said lead or catheter disposed therethrough. 
     
     
       3. The introducer system of claim 2 wherein said means for splitting said sheath comprise a first tab on a first side of said second end of said sheath, and a second tab on a second side of said second end of said sheath whereby, when said tabs are pulled apart, said sheath tears longitudinally separating said sheath from said lead or catheter disposed therethrough. 
     
     
       4. The introducer system of claim 2 wherein said means for splitting said sheath comprises a weakened section extending longitudinally from said first end to said second end of said sheath. 
     
     
       5. The introducer system of claim 4 wherein said weakened section comprises a score line. 
     
     
       6. The introducer system of claim 4 wherein said weakened section comprises a section of material having the physical property of molecular orientation whereby a tear in said material runs readily only in a longitudinal direction along the length of said sheath. 
     
     
       7. The introducer system of claim 1 wherein said flexible kink resistant section is smooth on its outer surface permitting said sheath to be slid through tissue of said body. 
     
     
       8. The introducer system of claim 1 wherein said flexible kink resistant section comprises a helical pleat on said outer surface of said sheath, said helical pleat permitting a portion of said sheath to be screwed through tissue of said body. 
     
     
       9. The introducer system of claim 1 further comprising said flexible kink resistant section being continuously smooth on its inner surface. 
     
     
       10. The introducer system of claim 1 further comprising said flexible kink resistant section comprising at least two pleats on said inner surface to increase the flexibility of said section. 
     
     
       11. The introducer system of claim 1 further comprising said flexible kink resistant section comprising at least two pleats on said outer surface to increase the flexibility of said section. 
     
     
       12. The introducer system of claim 1 further comprising said flexible kink resistant section comprising at least two pleats on said outer surface and further comprising at least two pleats on said inner surface. 
     
     
       13. The introducer system of claim 1 wherein said flexible kink resistant section comprises a series of bellows. 
     
     
       14. The introducer system of claim 1 in which the material is a plastic. 
     
     
       15. The introducer system of claim 1 in which the material is polytetrafluoroethylene. 
     
     
       16. The introducer system of claim 1 in which said first end of said sheath is tapered so as to define a tapered end portion, said sheath having an inner surface and an outer surface and having a substantially uniform thickness from the inner surface to the outer surface except at the tapered end portion and the flexible kink resistant section. 
     
     
       17. An introducer system for use with a catheter or lead comprising: a sheath having a first end and a second end, said sheath further having a proximal span, an intermediate span and a distal span, said proximal span and said distal span having approximately equal length, said first end having means for inserting said sheath within said body with said second end extending out of said body, said sheath having a central lumen configured to permit introduction of at least one lead or catheter therethrough;   a flexible kink resistant section located along said intermediate span;   means for permitting removal of said sheath from said lead or catheter disposed therethrough without requiring said sheath to be removed from an end of said lead or catheter disposed therethrough; and   a dilator having a first end and a second end, said first end of said dilator being tapered, said dilator disposed through said central lumen of said sheath.   
     
     
       18. The introducer system of claim 17 wherein said means for permitting removal of said sheath comprises means for splitting said sheath away from said lead or catheter disposed therethrough. 
     
     
       19. The introducer system of claim 18 wherein said means for splitting said sheath comprise a first tab on a first side of said second end of said sheath, and a second tab on a second side of said second end of said sheath whereby, when said tabs are pulled apart, said sheath tears longitudinally separating said sheath from said lead or catheter disposed therethrough. 
     
     
       20. The introducer system of claim 18 wherein said means for splitting said sheath comprises a weakened section extending longitudinally from said first end to said second end of said sheath. 
     
     
       21. The introducer system of claim 20 wherein said weakened section comprises a score line. 
     
     
       22. The introducer system of claim 20 wherein said weakened section comprises a section of material having the physical property of molecular orientation whereby a tear in said material runs readily only in a longitudinal direction along the length of said sheath. 
     
     
       23. The introducer system of claim 17 wherein said flexible kink resistant section is smooth on its outer surface permitting said sheath to be slid through tissue of said body. 
     
     
       24. The introducer system of claim 17 wherein said flexible kink resistant section comprises a helical pleat on said outer surface of said sheath, said helical pleat permitting a portion of said sheath to be screwed through tissue of said body. 
     
     
       25. The introducer system of claim 17 further comprising said flexible kink resistant section being continuously smooth on its inner surface. 
     
     
       26. The introducer system of claim 17 further comprising said flexible kink resistant section comprising at least two pleats on said inner surface to increase the flexibility of said section. 
     
     
       27. The introducer system of claim 17 further comprising said flexible kink resistant section comprising at least two pleats on said outer surface to increase the flexibility of said section. 
     
     
       28. The introducer system of claim 17 further comprising said flexible kink resistant section comprising at least two pleats on said outer surface and further comprising at least two pleats on said inner surface. 
     
     
       29. The introducer system of claim 17 wherein said flexible kink resistant section comprises a series of bellows. 
     
     
       30. The introducer system of claim 17 in which the material is a plastic. 
     
     
       31. The introducer system of claim 17 in which the material is polytetrafluoroethylene. 
     
     
       32. The introducer system of claim 17 in which said first end of said sheath is tapered so as to define a tapered end portion, said sheath having an inner surface and an outer surface and having a substantially uniform thickness from the inner surface to the outer surface except at the tapered end portion and the flexible kink resistant section. 
     
     
       33. The introducer system of either claims 1 or 17 further comprising means for inhibiting blood flow through said sheath positioned on a proximal end of said sheath. 
     
     
       34. A method of introducing a body implantable lead comprising the steps of: introducing a percutaneous needle having a central lumen through a patient's skin and into said patient's blood vessel;   introducing a wire guide through said central lumen and into said patient's blood vessel;   providing a rigid dilator through a lumen of an introducer sheath having a kink resistant section;   introducing said rigid dilator and introducer sheath into said patient's blood vessel a first distance, wherein said introducer sheath is straight;   withdrawing said rigid dilator from said lumen of said introducer sheath;   introducing said introducers sheath from said first distance, wherein said rigid dilator and introducer sheath are straight, to a second distance within said patient's blood vessel, wherein said introducer sheath is bent at along said kink resistant section; and   introducing a body implantable lead through said introducer sheath into said patient's blood vessel.   
     
     
       35. The method according to claim 34 further comprising the step of removing said introducer sheath from said patient's blood vessel without removing said sheath from over an end of said lead. 
     
     
       36. A method of introducing a body implantable lead comprising the steps of: introducing a percutaneous needle having a central lumen through a patient's skin and into said patient's blood vessel;   introducing a wire guide through said central lumen and into said patient's blood vessel;   providing a rigid dilator through a lumen of an introducer sheath having a bellowed section;   introducing said rigid dilator and introducer sheath into said patient's blood vessel a first distance, wherein said introducer sheath is straight;   withdrawing said rigid dilator from said lumen of said introducer sheath;   introducing said introducer sheath from said first distance, wherein said rigid dilator and introducer sheath are straight, to a second distance into said patient's blood vessel wherein said introducer sheath is bent along said bellowed section;   introducing a body implantable lead through said introducer sheath into said patient's blood vessel; and   removing said introducer sheath from said patient's blood vessel without removing said sheath from over an end of said lead.   
     
     
       37. The method of either claims 34 or 36 further comprising the step of providing on a proximal end of said sheath means for inhibiting blood flow through said sheath.